Added a How to Use section in the README.
Added a How to Use section in the README.

ianlet/rust-design-patterns,beni55/rust-design-patterns,ianlet/rust-design-patterns,jdavis/rust-design-patterns,jdavis/rust-design-patterns,jdavis/rust-design-patterns,jdavis/rust-design-patterns,ianlet/rust-design-patterns,beni55/rust-design-patterns,beni55/rust-design-patterns